This invention relates generally to the field of machining and relates more particularly to the lubrication and/or cooling of the surface of a workpiece while the workpiece is being cut by a rotating cutting tool. Cutting processes with which this invention is concerned include such processes as drilling, end milling, rotary cutting, countersinking and tapping in which a cutting tool is rotated about a rotational axis and moved in and relative to the workpiece to effect a cutting operation.
It is known that for purposes of lubricating and/or cooling a workpiece during a cutting operation, a suitable fluid such as oil or water can be directed toward the region of engagement between the cutting tool and the workpiece. However, common methods and equipment for directing the fluid toward the aforesaid region of engagement are generally limited in capacity to effectively introduce fluid into the region of the workpiece at which the cutting operation is effected that is, the workpiece region being cut by the cutting edge of the cutting tool. For example, in conventional drilling apparatus utilizing a twist drill for drilling a hole, a lubricating and/or cooling fluid is commonly directed toward the edge or entrance of the hole while the drilling process is underway. However, with the drill rotating within the hole, the directed fluid does not effectively reach the workpiece region (e.g., the bottom of the hole) at which the leading cutting edges of the drill engage the workpiece.
Accordingly, it is an object of the present invention to provide a new and improved apparatus for lubricating and/or cooling a workpiece during a cutting operation with a rotating cutting tool.
Another object of the present invention is to provide such an apparatus for effectively introducing a fluid into the region of engagement between the workpiece and the cutting edges of the cutting tool.
Still another object of the present invention is to provide such an apparatus wherein the pressures required to direct a lubricating and/or cooling fluid between the region of engagement between a workpiece and a cutting tool are relatively low.
Yet still another object of the present invention is to provide such an apparatus which is economical to manufacture and effective in operation.